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find Keyword "Polymer" 33 results
  • Infected endophthalmitis diagnosed by multiplex polymerase chain reaction

    Objective To evaluate the rapid diagnosis of bacterial and (or) fungal endophthalmitis by multiplex polymerase chain reaction (MPCR). Methods MPCR was performed to detect the DNA segment of bacteria and (or) fungi from standard strains and 41 samples of intraocular fluid or vitreous from 38 patients (3 with double eyes and 35 with single), and the results were compared with the cultured bacteria and fungi. Results Five hours after detected by MPCR, bacteria and (or) fungi in 34 out of 41 samples (82.9%) from patients were detected,in cluding bacteria in 26,fungi in 6,and both bacteria and fungi in 2. The positive rate of MPCR was obviously higher than the cultured ones(χ2=9.60, P<0.05). Conclusion With the advantages of rapidity, sensibility, and specificity, MPCR can make for the rapid and definitive diagnosis of bacterial and (or) fungal endophthalmitis. (Chin J Ocul Fundus Dis,2004,20:81-83)

    Release date:2016-09-02 05:58 Export PDF Favorites Scan
  • Mutation and Expression of β-Catenin Gene in Breast Hyperplasia and Breast Cancer

    Objective To investigate the role of β-catenin gene in breast tumorigenesis by detecting mutation and expression of β-catenin gene in breast hyperplasia and breast cancer. Methods Mutation and expression of β-catenin gene in 42 breast cancer, 15 simple hyperplasia and 15 atypical hyperplasia were detected by polymerase chain reaction-single strand conformation polymorphism and immunohistochemistry. Results Normal expression of β-catenin occurred in tissue of breast simple hyperplasia. The rate of abnormal expression of β-catenin in tissue of breast atypical hyperplasia and breast cancer were 26.7% (4/15) and 59.5% (25/42), respectively, which were higher than that of simple hyherplasia tissue (P<0.05). And there was a markedly difference between the atypical hyperplasia tissue and breast cancer tissue (P<0.05). Mutation of β-catenin gene wasn’t detected in this three kinds of tissues. Conclusion Abnormal expression of β-catenin plays an important role in human breast tumorigenesis, reason of abnormal expression of β-catenin isn’t mutation of β-catenin gene. Expression of β-catenin can be regulated by other mechanisms.

    Release date:2016-08-28 04:08 Export PDF Favorites Scan
  • Molecular biological detection of leber is hereditary optic neuropathy

    Purpose To investigate the relationship between mitochondrial DNA 11778 mutation and clinical characteristics of patients with Laber is hereditary optic neuropathy(LHON). Methods PCR RFLPs (MaeⅢ) and mutation specific primer PCR(MSP-PCR) were used simultaneously to detect mitochondrial DNA 11778 mutation. Results Among 10 subjects who habored 11778 mutation,one was a carrier and nine were patients with LHON.Of the nine patients,six were males and three were females.The age of onset ranged from 12 to 25 years old and the onset interval of the two eyed varied between 0 to 6 months. The visual acuity was CF/10cm-0.1 except one who lost her vision after delivery but recovered gradually.The results of visual field,VEP and color vision were abnormal but ERG and systemic status were all normal. Conclusion Molecular biological detection of the ten subjects showed that they all habored mtDNA 11778 mutation.The existence of carrier and visual recovery imlied that mtDNA mutation was a primary cause of LHON,but other factors such as endocrine disorder might influence the pathogenesis of LHON. (Chin J Ocul Fundus Dis,1998,14:156-158)

    Release date:2016-09-02 06:11 Export PDF Favorites Scan
  • THE RYR1 GENOTYPE OF CHINESE INBRED PIGS

    OBJECTIVE: Porcine stress syndrome (PSS) is one kind of molecular genetics defect diseases of pig which will cause malignant hyperthermia syndrome (MHS) and is the first index should be excluded in screening of a pig species for xenotransplantation. It was reported that mutation of pig rynodine receptor(RYR1) gene is the main reason for PSS. In this study, RYR1 genotypes of the Chinese Banna mini pig inbred line and inbreeding closed colony Wuzhishan pig were investigated with polymerase chain reaction-restriction endonuclease fragment length polymorphism (PCR-RFLP) technique. METHODS: Antevenocaval whole blood samples were collected from 50 Banna mini-pig inbred-line(BMI), 15 inbreeding Wuzhishan pig (WZSP) and 25 Neijiang pigs (NJP) as negative control, the primer were designed and synthesized, PCR reaction was conducted following the sequence of 94 degrees C (1 min), 58 degrees C (1 min) and 72 degrees C (1 min) for 30 cycles. The PCR products were digested with restriction endonuclease HhaI and then electrophoresis check. RESULTS: A 659 bp DNA fragment was amplified with these two primers, the HALNN sample fragment was cut into fragments as 493 bp and 166 bp individually after the digestion, indicates no point mutation at site 1,843 in RYR1 gene in all tested BMI pig and WZSP. Namely, the RYR1 genotype of 50 cases of BMI and 15 cases of WZSP were HALNN, therefore their phenotype is PSS negative. CONCLUSION: It indicates that the genotype of Banna mini pig inbred line and inbreeding Wuzhishan pig are HALNN therefore PSS absolutely negative, the group penetrance is 0. This is consistent with experimental observation. It suggests that Banna mini pig inbred line and inbreeding Wuzhishan pig may be the alternative donor for xenotransplantation.

    Release date:2016-09-01 10:27 Export PDF Favorites Scan
  • mRNA EXPRESSION OF nm23-H1 GENE IN HUMAN LIVER TUMOR ASSAYED BY REVERSE TRANSCRIPTIONPOLYMERASE CHAIN REACTION

    To investigate the mRNA expression of nm23-H1 gene in human liver tumor. In tumor and corresponding nontumoral liver specimens from 20 patients, nm23-H1 mRNA were examined by reverse transcriptionpolymerase chain reaction (RT-PCR) method with specific primers. Results: The primers designed in this study could amplified nearly entire coding sequence of nm23-H1 gene. All the samples showed positive expression of nm23-H1 mRNA, indicating there was no expression loss or obvious alteration. Conclusions: The achievement of RT-PCR method lays foundation for quantitative gaugement of nm23-H1 mRNA in liver tumor.

    Release date:2016-08-29 09:20 Export PDF Favorites Scan
  • Joint Detection of hTERT mRNA and GGT mRNA-H Expressions in Peripheral Blood of Small Hepatocellular Carcinoma Patients and Its Clinical Significance

    ObjectiveTo investigate the expressions and clinical significance of human telomerase reverse transcriptase (hTERT) mRNA and γglutamyl transpeptidase mRNA-H (GGT mRNA-H) in the peripheral blood of small hepatocellular carcinoma (HCC) patients. MethodsThe expressions of hTERT mRNA and GGT mRNA-H were detected in the peripheral blood of thirty patients with small HCC by RT-PCR, eighteen patients with benign liver diseases, and twelve normal volunteers. ResultsThe positive rate of hTERT mRNA and GGT mRNA-H expression in patients with small HCC were 80.0% (24/30) and 46.7%(14/30), respectively. In patients with hepatitic cirrhosis the positive rate of hTERT mRNA expression was 33.3% (6/18), while the expression of GGT mRNA was not detected. Both the expressions of hTERT mRNA and GGT mRNA-H were negative in all normal volunteers. The combination analysis of hTERT mRNA and GGT mRNA-H expression achieved positive rate of 86.7% in the diagnosis of small HCC, which was significantly higher than the positive rate of AFP (26.7%), Plt;0.05. ConclusionThe hTERT mRNA and GGT mRNA-H are significantly expressed in small HCC patients, the combination analysis of hTERT mRNA and GGT mRNA-H seems to be useful in the early diagnosis of small HCC.

    Release date:2016-09-08 10:46 Export PDF Favorites Scan
  • The relationship between vitamin D receptor gene TaqⅠpolymorphism and diabetic retinopathy

    Objective To investigate the polymorphism of the vitamin D receptor gene (VDR)TaqⅠin relation to diabetic retinopathy. Method Fragment length discrepant allele specific PCR(FLDAS-PCR) were used to determine VDR genetypes in 158 patients with diabetic retinopathy and in 198 normal subjects. Results The frequency distribution of VDR genotypes in diabetic retinopathy patients was 106 (67.1%) in TT, 33(20.9%) in Tt, 19(12.0%) in tt; and in normal persons was 165 (83.3%) in TT, 23(11.6%) in Tt, 10 (5.1%) in tt. There was a significant difference between diabetic retinopathy patients and normal persons in distribution of VDR gene TaqⅠgenotypes(Plt;0.05). Conclusions There is some distribution alterations of VDR gene polymorphism in diabetic retinopathy patients. (Chin J Ocul Fundus Dis, 2006, 22: 94-96)

    Release date:2016-09-02 05:51 Export PDF Favorites Scan
  • Primary mutation detection of mitochondrial DNA(mtDNA)in Leber′s hereditary optic neuropathy patients

    Optic atrophy,hereditary/diagnosis; Polymerase chain reaction; DNA,mitochondrial; Point mutation; Sequence analysis

    Release date:2016-09-02 06:07 Export PDF Favorites Scan
  • Search for mutations of the rhodopsin gene in patients with autosomal dominant retinitis pigmentosa

    Objective To investigate whether mutations exist in codon 58 and codon 347 of the rhodopsin gene in patients with autosomal dominant retinitis pigmentosa(ADRP). Methods Point mutations at codons 58 and 347 were detected by restriction endonuclease digestion of exons 1 and 5 amplified by polymerase chain reaction(PCR).This method was applied to screen genomic DNAs from 57 patients of 38 families with ADRP and 60 normal controls. Results Four patients from one family of ADRP were confirmed to have a point mutation at the second nucleotide of codon 58,and 6 patients from two families of ADRP were found to have a mutation at codon 347.None of these mutations were found in 60 normal subjects. Conclusion It is suggested that molecular genetic heterogeneity exists within ADRP and some subtypes of ADRP are caused by points mutations of the rhodopsin gene. (Chin J Ocul Fundus Dis,1998,14:108-110)

    Release date:2016-09-02 06:11 Export PDF Favorites Scan
  • Artificial Coronary Vascular Stents Fabrication Using Biodegradable Material Compounds of PLA/PGA-co-Chitosan

    Abstract: The first generation scaffolds of bare metal stents (BMS) and the second generation of drug eluting stents (DES) have been widely used in the treatment of coronary heart diseases. However, long term incidences of major adverse cardiovascular events and revascularization treatments are still high because of in-stent re-stenosis and thrombosis. These may be caused by chronic inflammations and vascular wall damages due to persistent metal stents stimulation. What’s more, the eluting drugs within metal stents could also disturb normal growth of vascular endothelial cell, intima, tunica media, smooth muscle and epimysium. Therefore, in order to meet these demands several fully biodegradable scaffolds and drug carried stents have been manufactured using polymers polyester, polycarbonate and polyphosphate, etc. Among them, the security and histo-and hemo-compatibilities of coronary scaffolds made from poly-lactic acid (PLA), poly-glycolic acid(PGA), chitosan as coating, poly-caprolactone (PCL) and other copolymer like poly-lactic-co-glycolic acid (PLGA) have been testified to be sound. Nevertheless, there exist several different shortages for these stents such as tensile strength deficiency and slow degradation. PLA is hard and brittle with slow degradation, while PGA is soft with insufficient support force and fast degradation. Whether stents degrade too fast or too slow, they could not supply sufficient strength and effective support after implantation, and also they may cause target vascular injuries and elastic shrink inducing restenosis and thrombosis in long terms. Using optimized molar ratio component of PLA and PGA with chitosan coating, we can get sound composite materials with better biocompatibility, moderate degradation (approximately 3 - 6 months of completedegradation), adequate mechanical strength, lower inflammatory response and good range of extension, and establish an experiment ground for fully biodegradable vascular scaffolds fabrication.

    Release date:2016-08-30 05:50 Export PDF Favorites Scan
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